Control valve assembly

ABSTRACT

Embodiments of the invention provide a control valve assembly and method of operating in a blend position at which a supply fluid and a treated fluid are combined into a blended fluid that is directed from the control valve assembly to establish multi-port blending. The control valve assembly is adjustable to accommodate fluctuating demand for treated fluid.

BACKGROUND OF THE INVENTION

Valves are used in a wide variety of applications to generally controland/or direct the flow of fluids. In one example application, valves areused to control the flow of water through water treatment systemsinstalled in residential and/or commercial settings. These watertreatment systems include, for instance, water treatment devices such aswater filters and conditioners that extract and/or replace undesirableconstituents in the supplied water.

One type of water treatment device, generally referred to as acapacitive deionization device, can be used to removeelectrically-charged impurities, such as ions, from a water supply. Incapacitive deionization devices, a stream of water passes through one ormore flow-through capacitors that include pairs of polarized electrodeplates. To remove impurities from the supply water passing between theelectrode plates, a voltage potential is established between theelectrode plates that causes many impurities in the supply water to beattracted to and (at least temporarily) retained on one of the electrodeplates, while the comparatively purified water flows from the capacitor.

The efficiency and capacity of the electrode plates are reduced duringuse as impurities extracted from the supply water increasingly saturatethe electrode plates. To regenerate the capacity of a flow-throughcapacitor, the flow-through capacitor can be set to discharge thecaptured impurities by removing the voltage potential or by temporarilyapplying a voltage potential in an opposite polarity to the voltagepotential established during purification. During discharge, theeffluent water carrying the impurities is typically routed to a drainline.

In general, the maximum flow rate of treated water from a capacitivedeionization device is limited by the physical surface area available totreat the supply water. In other words, to increase the real-time flowrate of treated water, the physical size of the capacitive deionizationdevice must be increased (e.g., with additional or larger flow-throughcapacitors) or a storage vessel (e.g., a hydropneumatic tank) must beincorporated to store treated water for later use. Either approach isinefficient, bulky, and adds cost to the overall system. Other types ofwater treatment systems suffer from similar drawbacks in that theultimate capacity or throughput is limited and related to the size ofthe overall system.

SUMMARY OF THE INVENTION

In light of at least the above, a need exists for a control valveassembly incorporating an improved design concept that can accommodatethe fluctuating demand placed on water treatment systems.

A control valve assembly capable of being in fluid communication with apoint of entry providing a supply fluid, a fluid treatment devicedefining a treatment inlet port for receiving the supply fluid and atreatment outlet port for supplying a treated fluid, and a point of use,comprises a valve body. The valve body includes a supply port in fluidcommunication with the point of entry to direct the supply fluid fromthe point of entry to the valve body; an outlet port in fluidcommunication with the treatment inlet port to direct the supply fluidfrom the valve body to the fluid treatment device; an inlet port influid communication with the treatment outlet port to direct the treatedfluid from the fluid treatment device to the valve body; and a serviceport in fluid communication with the point of use to direct at least oneof the supply fluid and the treated fluid from the valve body to thepoint of use. A valve is seated within the valve body and is movable toa blend position at which both the supply fluid and the treated fluidare directed through the service port so that a blended fluid includingthe supply fluid and the treated fluid is directed from the valve bodyto the point of use.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of an example control valve assembly coupledto an example water treatment device.

FIG. 2 is a bottom isometric view of the example control valve assembly.

FIG. 3 is a bottom plan view of the example control valve assembly.

FIG. 4 is an end plan view of the example control valve assembly.

FIG. 5 is a left side plan view of the example control valve assembly.

FIG. 6 is a right side plan view of the example control valve assembly.

FIG. 7 is a top plan, partial section view of the example control valveassembly.

FIG. 8 is a partially exploded, isometric view of the example controlvalve assembly illustrating example pressure sensors and exampleconductivity sensors.

FIG. 9 is a partially exploded, isometric view of the example controlvalve assembly illustrating an example check valve and an example flowmeter.

FIG. 10 is a partial isometric view of an example gear train of theexample control valve assembly.

FIG. 11 is an isometric view of a portion of the example control valveassembly.

FIG. 12 is a section view along line 12-12 shown in FIG. 11 illustratingthe portion of the example control valve assembly in an example valvechamber.

FIG. 13A is a plan view of an example piston shown in FIGS. 11 and 12.

FIG. 13B-13E are partial plan views of alternative example pistons.

FIG. 14 is a section view along line 14-14 shown in FIG. 4 illustratingthe example control valve assembly in an off position.

FIG. 15 is a section view along line 15-15 shown in FIG. 4 illustratingthe example control valve assembly in the off position shown in FIG. 14.

FIG. 16 is a section view illustrating the example control valveassembly in a service position.

FIG. 17 is a section view illustrating the example control valveassembly in the service position shown in FIG. 16.

FIG. 18 is a section view illustrating the example control valveassembly in a blend position.

FIG. 19 is a section view illustrating the example control valveassembly in the blend position shown in FIG. 18.

FIG. 20 is a section view illustrating the example control valveassembly in a drain position.

FIG. 21 is a section view illustrating the example control valveassembly in the drain position shown in FIG. 20.

FIG. 22 is a detail view of the portion of FIG. 21 circumscribed by arc22-22 shown in FIG. 21.

FIG. 23 is an isometric view of an alternative example control valveassembly.

FIG. 24 is a partial section view along line 24-24 shown in FIG. 23 ofthe alternative example control valve assembly.

FIG. 25 is a partial section view of the alternative example controlvalve assembly in an off position.

FIG. 26 is a partial section view of the alternative example controlvalve assembly in a service position.

FIG. 27 is a partial section view of the alternative example controlvalve assembly in a blend position.

FIG. 28 is a partial section view of the alternative example controlvalve assembly in a bypass position.

FIG. 29 is a partial section view of the alternative example controlvalve assembly in a drain position.

FIG. 30 is a schematic of an example fluid treatment system.

FIG. 31 is a schematic of an example control valve assembly.

FIG. 32 is a flow chart illustrating operation of an example controlvalve assembly.

FIG. 33 is a partial cross section view of an alternative motorconfiguration.

FIG. 34 is a partial section view of an example capacitive deionizationdevice including an example control valve assembly.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways. Also, it is to be understood thatthe phraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including,” “comprising,” or “having” and variations thereof herein ismeant to encompass the items listed thereafter and equivalents thereofas well as additional items. Unless specified or limited otherwise, theterms “mounted,” “connected,” “supported,” and “coupled” and variationsthereof are used broadly and encompass both direct and indirectmountings, connections, supports, and couplings. Further, “connected”and “coupled” are not restricted to physical or mechanical connectionsor couplings.

The following discussion is presented to enable a person skilled in theart to make and use embodiments of the invention. Various modificationsto the illustrated embodiments will be readily apparent to those skilledin the art, and the generic principles herein can be applied to otherembodiments and applications without departing from embodiments of theinvention. Thus, embodiments of the invention are not intended to belimited to embodiments shown, but are to be accorded the widest scopeconsistent with the principles and features disclosed herein. Thefollowing detailed description is to be read with reference to thefigures, in which like elements in different figures have like referencenumerals. The figures, which are not necessarily to scale, depictselected embodiments and are not intended to limit the scope ofembodiments of the invention. Skilled artisans will recognize theexamples provided herein have many useful alternatives and fall withinthe scope of embodiments of the invention.

One embodiment of a control valve assembly with multi-port blending(“control valve assembly 10”) is described in the context of a fluidtreatment device. The fluid treatment device is shown and described inthe form of a capacitive deionization device 12. However, theembodiments described herein can be incorporated into other suitabletypes of fluid treatment devices, such as an electrodeionization device,a continuous electrodeionization device, an electrodialysis device, acapacitive deionization device including a flow-through capacitor, acarbon filter device, a reverse osmosis device, or a water softenerdevice (e.g., including a resin bed). In one embodiment, anelectrodeionization device performs a process that uses electricallyactive media and electrical potential to influence ion movement within aliquid. Electrodeionization devices can include media that has apermanent or a temporary charge and is operated to cause electrochemicalreactions, with or without electrically active membranes (e.g.,semi-permeable ion exchange or bipolar membranes). Continuouselectrodeionization devices incorporate a process typically includingalternating electroactive semi-permeable anion and cation exchangemembranes. Fluid flows between the membranes and a DC electrical fieldis supplied to attract ions to respective electrodes. Electrodecompartments can be included to separate reaction product from the otherflow compartments. In general, embodiments of the invention can beincorporated into a fluid treatment system that is susceptible tofluctuating demands for treated water.

FIG. 1 illustrates the control valve assembly 10 in fluid communicationwith the capacitive deionization device 12. The control valve assembly10 is configured to control the flow of supply fluid and treated fluidthrough the control valve assembly in response to fluctuating fluiddemands. The capacitive deionization device 12 includes a container 14that houses the various water treatment components (e.g., flow-throughcapacitors). The container 14 tappers to an upper neck 16 that definesan outer, circular treatment inlet port 18 and an inner, circulartreatment outlet port 20 that is nested radially inward of the treatmentinlet port 18. Alternatively, various other fluid treatment devices canbe configured in fluid communication with the control valve assembly 10,and the structure of the control valve assembly 10 can be modified toestablish the application specific fluid communication.

FIGS. 2 and 3 illustrate that the control valve assembly 10 is coupledto the upper neck 16 by a collar 22. The collar 22 is sized to receivethe upper neck 16 of the container 14 and is coupled to an annular lipof the upper neck 16 by a split lock ring 24. The lock ring 24 hascircumferentially spaced tabs 26 that extend radially inward from anouter band 28 of the split lock ring 24. When seated, the tabs 26 extendthrough aligned rectangular slots 29 formed through the collar 22 andengage the annular lip of the upper neck 16, thus inhibiting removal ofthe control valve assembly 10 from the capacitive deionization device12. One or more seals can be arranged between the upper neck 16 and thecollar 22 to prevent undesirable fluid leakage at the coupling.

Coupling the control valve assembly 10 to the capacitive deionizationdevice 12 places respective ports of the control valve assembly 10 intofluid communication with the treatment inlet port 18 and the treatmentoutlet port 20, thus establishing passageways for fluid communication.As shown in FIGS. 2 and 3, the control valve assembly 10 includes aninner tube 32 that is coaxially aligned with an outer tube 34 defined bythe collar 22. When the control valve assembly 10 is seated on the upperneck 16, the inner tube 32 is brought into fluid communication with thetreatment outlet port 20 and the outer tube 34 is similarly brought intofluid communication with the treatment inlet port 18. The inner tube 32is sealed with the treatment outlet port 20 so that a supply fluidflowing from the control valve assembly 10 into the capacitivedeionization device 12 is inhibited from mixing with a treated fluidflowing out of the capacitive deionization device 12. A flow path isdefined from the outer tube 34 of the control valve assembly 10, intothe treatment inlet port 18, through the capacitive deionization device12, out of the treatment outlet port 20, and into the inner tube 32 ofthe control valve assembly 10.

The collar 22, the outer tube 34, and the inner tube 32 extend from avalve body 38 of the control valve assembly 10. As shown in FIG. 3, thevalve body 38 defines an outlet port 40 and an inlet port 42 that bothprovide fluid communication into a valve chamber 44 (as also shown inFIGS. 12 and 14-21. Furthermore, the outlet port 40 also establishesfluid communication with the outer tube 34 and the correspondingtreatment inlet port 18; similarly, the inlet port 42 establishes fluidcommunication with the inner tube 32 and corresponding treatment outletport 20. As a result, in one mode of operation, the treatment inlet port18 will receive a supply fluid from the control valve assembly 10. Thesupply fluid can flow through the balance of the capacitive deionizationdevice 12 to be treated. A treated fluid can then flow out of thecapacitive deionization device 12 through the treatment outlet port 20back into the control valve assembly 10.

The control valve assembly 10 can be in fluid communication with a pointof entry (e.g., a residential or commercial water source, such as awell, pressure tank, municipal connection, an upstream fluid treatmentdevice, etc.) that provides the supply fluid, and a point of use (e.g.,a residential or commercial water service, such as a water heater,potable water spigot, a downstream fluid treatment device, etc.) thatreceives the fluid (e.g., treated, untreated, partially treated,blended, etc.) that flows from the control valve assembly 10. As shownin FIGS. 4, 7, 14, 16, 18, and 20, the valve body 38 of the controlvalve assembly 10 defines a supply port 46 and a service port 48 thatprovide the fluid communication between the control valve assembly 10and the respective point of entry and point of use. In some embodiments,the valve body 38 can be made, for example, from brass, stainless steel,plastics, or composites, and can be constructed, for instance, bycasting, machining, or molding.

FIGS. 4-8 illustrate a manual bypass body 50 that is coupled to thecontrol valve assembly 10 and connects to a supply conduit and a serviceconduit. The manual bypass body 50 is generally H-shaped and defines acylindrical external supply port 52 and a cylindrical external serviceport 54, which are configured to couple with the supply conduit and theservice conduits, respectively. The external supply port 52 defines asupply chamber 56 and the external service port 54 defines a similarservice chamber 58. A bypass chamber 60 extends between the supplychamber 56 and the service chamber 58, so that fluid can be directedthrough the bypass chamber 60 when a supply valve 62 and a service valve64 are oriented accordingly.

The supply valve 62 is rotatably seated within the supply chamber 56 sothat the supply valve 62 can be rotated ninety-degrees between aflow-through position (shown in FIG. 7) and a divert position. When thesupply valve 62 is in the flow-through position, fluid is allowed topass though the supply chamber 56 and into the supply port 46 of thecontrol valve assembly 10; in the divert position, fluid is inhibited bythe supply valve 62 from flowing into the supply port 46 and is insteadredirected into the bypass chamber 60. Similarly, the service valve 64is rotatably seated within the service chamber 58 so that the servicevalve 64 can be rotated ninety-degrees between a flow-through position(shown in FIG. 7) and a divert position. When the service valve 64 is inthe flow-through position, fluid is allowed to pass though the servicechamber 58 from the service port 54 of the control valve assembly 10; inthe divert position, fluid is inhibited by the service valve 64 fromflowing from the service port 54 but fluid within the bypass chamber 60is directed into the service chamber 58. The supply chamber 56 alsodefines an auxiliary port 66 (shown covered by a cap 68) that can beconnected in fluid communication with an auxiliary device (e.g., adrain).

The manual bypass body 50 further includes a cylindrical supply tube 70and a cylindrical service tube 72 that are coupled to the valve body 38by U-clips 74, 76. The supply tube 70 is slid over the supply port 46and the service tube 72 is slid over the service port 48, then therespective U-clips 74, 76 are inserted into openings 78 through themanual bypass body 50 to seat in a series of cylindrical openings 80formed in the valve body 38. The engagement between the U-clips 74, 76,the manual bypass body 50, and the valve body 38 restrains the manualbypass body 50.

The manual bypass body 50 can be made, for example, from brass,stainless steel, plastics, or composites, and can be constructed, forinstance, by casting, machining, or molding. In other embodiments, themanual bypass body 50 (and/or its function) can be integral with thevalve body 38.

The control valve assembly 10 also includes a series of sensors that arepositioned within the valve body 38 to monitor various properties of thefluid flowing into, through, and/or out of the control valve assembly10. Other sensors can be incorporated in the overall fluid treatmentsystem to monitor additional properties of the system, such as anambient temperature and a fluid level or pressure within a treated waterstorage vessel. The sensors monitor aspects of operation and communicateparameters indicative of operation to a controller (e.g., a computer,programmable logic controller, a microcontroller, etc.). In someembodiments, the controller can control the operation of the controlvalve assembly 10 in response to and in view of those sensed parameters,as is described below in more detail. In one embodiment, the controllercan be monitoring sensors for parameters that indicate the fluid demandis or will likely exceed the real-time flow capacity of the fluidtreatment device. The controller can operate the control valve assembly10 to move the control valve assembly 10 into a position, so that thefluid demand is fulfilled, albeit with partially treated (or blended)fluid. Many other control logics can be implemented and tailored to thespecific application, including the specifications of the fluidtreatment device and other devices incorporated into the overall fluidtreatment system.

As shown in FIG. 8, a supply pressure sensor 86, a service pressuresensor 88, a supply conductivity sensor 82, and a service conductivitysensor 84 are seated in respective sensor ports 94, 96, 90, 92 formed inthe valve body 38. The sensor ports 94, 96, 90, 92 extend into desiredlocations of a manifold 98 that is defined within the valve body 38, andthe control logic related to the sensors is discussed in greater detailbelow. The supply conductivity sensor 82 and the service conductivitysensor 84 are coupled to respective ports 90, 92 by individualmulti-prong clips 100, 102. Specifically, each multi-prong clip 100, 102includes resilient arms 104, 106 that are inserted into slots 108, 110formed in respective port collars 112, 114 that extend from the valvebody 38. As the multi-prong clips 100, 102 are slid into engagement withthe slots 108, 110, the resilient arms 104, 106 flex about therespective bodies 116, 118 of the supply conductivity sensor 82 and theservice conductivity sensor 84 until arcuate surfaces 120, 122 conformto a circumferential groove 124, 126 in the bodies 116, 118. Eachmulti-prong clip 100, 102 also includes a central split prong 128, 130that seats into a central slot 132, 134 formed in the respective portcollar 112, 114.

Similarly, the supply pressure sensor 86 and the service pressure sensor88 are coupled to respective port collars 136, 138 formed by the valvebody 38. Each port collar 136, 138 defines a pair of standoffs 140, 142that define respective cylindrical openings 144, 146 into which U-shapedclips 148, 150 are inserted. The U-shaped clips 148, 150 includeopposing arms 152, 154 that extend into circumferential grooves 156, 158formed in bodies 160, 162 of the supply pressure sensor 86 and theservice pressure sensor 88.

The communication connections are not shown in FIG. 8 for clarity,however, the supply pressure sensor 86, the service pressure sensor 88,the supply conductivity sensor 82, and the service conductivity sensor84 can be in communication (e.g., wired, wireless, one-way, two-way,etc.) with a controller, so that a representative parameter is providedby each sensor to the controller. The supply pressure sensor 86 and theservice pressure sensor 88 can be part number 2066 manufactured byMarquardt of Rietheim-Weilheim, Germany, and the supply conductivitysensor 82 and the service conductivity sensor 84 can be any suitableconductivity sensor having specifications that accommodate theparticular application requirements.

FIGS. 7 and 9 illustrate an additional sensor and a flow control devicebeing incorporated into the control valve assembly 10 (the manual bypassbody 50 has been removed in FIG. 9 for clarity). A flow meter 164 isseated within the supply port 46 and includes an outer shell 166 thathouses a series of guide vanes 168 and a rotatable blade ring 170. Theflow meter 164 can be part number GL3027839 manufactured by PentairResidential Filtration, LLC of Milwaukee, Wis. The valve body 38 definesa mount 172 in which a pickup is secured; the pickup can be incommunication with the controller to communicate a parameter indicatingthe flow of the supply fluid into the supply port 46 (e.g., flow or noflow, flow rate, etc.). A check valve 174 is seated within the serviceport 48 to inhibit backflow through the service port 48 into themanifold 98 of the control valve assembly 10. The check valve 174 can bepart number NV25-25M manufactured by Neoperl, Inc. of Waterbury, Conn.The manual bypass body 50 captures the flow meter 164 and the checkvalve 174 within the respective supply port 46 and the respectiveservice port 48 when the manual bypass body 50 is secured to valve body38, as described above and illustrated in FIG. 7.

A controller executing predefined logic can be configured to adjust theoperation of the control valve assembly 10 to alter how fluid flows (oris inhibited from flowing) through the manifold 98 of the valve body 38.In the control valve assembly 10, a motor in the form of an electricmotor 176 (e.g., a direct current electric motor having a magnetic Halleffect pickup in communication with the controller) is incorporated toultimately adjust the available flow passageways through the controlvalve assembly 10. The electric motor 176 can be a DC motor, an ACmotor, a stepper motor, and the like, such as part number GLBDC-1227-01manufactured by Global.

As shown in FIGS. 2 and 10, the electric motor 176 and a gear train 178are mounted to the valve body 38 so that, in some embodiments,rotational movement of the electric motor 176 results in translation ofa valve 180. The valve 180 is seated within the valve body 38intersecting the manifold 98 to alter or adjust the operation of thecontrol valve assembly 10. The valve body 38 forms a cylindricalmounting flange 182 with a series of fastener bores 184. A generallyrectangular mounting plate 186 is secured to the mounting flange 182with several fasteners 188, and a cover 190 is positioned over the geartrain 178 and secured to the mounting plate 186 by additional fasteners192. The cover 190 both shields the gear train 178 and provides amounting location for the electric motor 176. As shown in FIGS. 2 and 8,the cover 190 forms a cylindrical receptacle 194 having resilient arms196 that extend from the cover 190 to capture the electric motor 176 tothe cover 190. The resilient arms 196 define beveled tips 198 that camagainst the electric motor 176 during installation and undercuts 200that engage an end face 202 of the electric motor 176 when fully seatedin the cylindrical receptacle 194, thus capturing the electric motor176. The mounting plate 186 and the cover 190 can be made, for example,from brass, stainless steel, plastics, or composites, and can beconstructed, for instance, by casting, machining, or molding.

FIG. 10 illustrates the gear train 178 with the cover 190 removed. Theelectric motor 176 includes a drive motor gear 204 that is rotatablyfixed to an output shaft of the electric motor 176. The drive motor gear204 includes teeth 206 that mesh with a first stacked transfer gear 208.The first stacked transfer gear 208 includes an outer gear 210 adjacentto an inner gear 212, which is fixed to the outer gear 210, so that theteeth 206 of the drive motor gear 204 are positioned to mesh with theouter gear 210. The first stacked transfer gear 208 is rotatably securedto a first spindle standoff 214 extending from the mounting plate 186.In a similar manner, a second stacked gear 216 supported by a secondspindle standoff 218 meshes with both the first stacked transfer gear208 and a third stacked gear 220 supported by a third spindle standoff222. The third stacked gear 220 meshes with a fourth stacked gear 224supported by a forth spindle standoff 226, and the fourth stacked gear224 is in turn meshed with a fifth stacked gear 228 supported by a fifthspindle standoff 230. As a result, the gear train 178 transfers therotational movement of the electric motor 176 (in either rotationaldirection) to a positioning gear 232. The various gears can be, forinstance, machined, cast, formed from powder metal, or injection molded.

The positioning gear 232 works in combination with a longitudinal drivegear 242 to convert rotational motion of the electric motor 176 totranslational movement of the valve 180. The positioning gear 232 isfixed from translation and includes external gear teeth 234 that areengaged by the fifth stacked gear 228 and defines helical threads 236within a central bore 238. The helical threads 236 are configured toengage mating external threads 240 on the longitudinal drive gear 242that is rotationally fixed. The relative rotation of the positioninggear 232 will cause the longitudinal drive gear 242 to translate throughthe central bore 238 of the positioning gear 232.

FIGS. 11, 12, 14, and 15 illustrate the interaction between thepositioning gear 232, the longitudinal drive gear 242, and the valve180. The positioning gear 232 is inhibited from axial movement but isallowed to rotate. The positioning gear 232 is axially restrained orlaterally fixed as it is positioned between the cover 190 and aring-shaped bushing 244 seated on a ledge 246 defined by the mountingplate 186 (as shown in FIGS. 14 and 15). The cover 190 includes anannular, arcuate projection 248 that engages a mating annular, arcuaterecess 250 formed on an outside face 252 of the positioning gear 232.Similarly, the bushing 244 defines an annular, arcuate projection 254that engages another mating annular, arcuate recess 256 formed on aninside face 258 of the positioning gear 232. The sliding, rotationalengagement between the projections 248, 254 and the recesses 250, 256allows the positioning gear 232 to rotate and also inhibits translationalong a valve axis 260. Rotation of the longitudinal drive gear 242 isrestrained due to engagement between opposing slots 274 formed axiallyalong the longitudinal drive gear 242 (one of which is shown in FIG. 11)and pairs of mating rectangular protrusions 276, 277 (as shown in FIG.15) that extend from an internal surface 278, 279 of the cover 190 andthe mounting plate 186, respectively, into the respective slots 274.

As the positioning gear 232 is rotationally driven by the electric motor176 through the gear train 178, the internal helical threads 236 camagainst the external threads 240 on the longitudinal drive gear 242,thus translating the longitudinal drive gear 242 along the valve axis260. In order to move the valve 180 within the valve chamber 44, a rod262 connects the longitudinal drive gear 242 to a piston 264 that isslidably seated within a cartridge cage 266. Specifically, a drive end268 of the rod 262 defines a groove 270 and a head 272 that is capturedto the longitudinal drive gear 242. The longitudinal drive gear 242includes a pair of resilient arms 280 with fingers 282 that extendradially inward toward the groove 270 to capture the rod 262. The rod262 extends from the drive end 268 through an opening 284 in themounting plate 186 and into the valve chamber 44. The mounting plate 186further includes a cylindrical plug 286 that seats within an end 288 ofthe valve chamber 44. The cylindrical plug 286 includes an annulargroove 290 formed in an exterior annular surface 292 in which an o-ring294 is seated. The o-ring 294 seals between the groove 290 and aninterior surface 296 of the valve chamber 44. An end cup 298 is seatedin the cylindrical plug 286 and includes a smaller diameter nipple 300that extends into a smaller diameter cavity 302 in the cylindrical plug286 to capture another o-ring 304. This o-ring 304 is sized to engagethe rod 262 as the rod 262 is translated through the opening 284.

The rod 262 further defines a valve end 306 that is opposite to thedrive end 268 and configured to be captured to the piston 264. Whenseated, the piston 264 can be moved within the cartridge cage 266 alonga piston axis 308, which is generally collinear with the valve axis 260.As shown in FIG. 13A, the piston 264 is generally cylindrical andextends from a tip end 310 to a base end 312. At the base end 312, threeresilient arms 314 are circumferentially spaced about the base end 312and are canted radially inward whereat the resilient arms 314 arecoupled by a split ring 316. The resilient arms 314 and the split ring316 define an opening 318 that captures another head 320 formed near thevalve end 306 of the rod 262.

In the control valve assembly 10, the piston 264 is moveable within thecartridge cage 266 to various positions that adjust the flow of fluidthrough the control valve assembly 10. In order to define the variousflow passageways, the cartridge cage 266 is seated within the valvechamber 44 and the piston 264 is sized to slidably seat within thecartridge cage 266. The cartridge cage 266 includes multiple externalseals 322 to seal against an interior cylindrical surface 324 of thevalve chamber 44 and additional internal seals 326 to slidably sealagainst an exterior surface 328 of the piston 264.

The cartridge cage 266 includes multiple disc-shaped segments that aresnap-fit together to establish seats for the various external seals 322and the internal seals 326. Specifically, a circular end cap 330 isseated in the valve chamber 44 adjacent to an end wall 332 of the valvechamber 44. Resilient tabs 334 extend axially from an interior face 335of the end cap 330 and include interlocking tips 336 (e.g., an undercut)to engage an adjacent flow disc 338. A series of flow discs 338 areinterlocked with one or more adjacent flow discs 338. Each flow disc 338includes offset, first and second parallel plates 340, 342 connected bya series of longitudinal spokes 344 proximate interior rims 346, 348 ofeach plate 340, 342. Radial openings 350 are defined between the plates340, 342 and the spokes 344. In addition, an annular lip 351 extendsaxially from the second plate 342 to define a partial seat for anexternal seal 322 and an internal seal 326. A full seat is formed whenadjacent flow discs 338 are coupled. To couple the adjacent flow discs338, the resilient tabs 334 of a first flow disc 338 are aligned withand inserted into arcuate openings 352 (as shown in FIG. 15) formed inthe first plate 340 of an adjacent flow disc 338, so that theinterlocking tips 336 of the first flow disc 338 are engaged with thefirst plate 340 of the adjacent flow disc 338. An end spool 354 includesa first plate 356 similar to the first plates 340 of the flow discs 338,but includes a solid second plate 358 that is coupled to the first plate356 by a solid cylindrical wall 360.

The bushing 244, the rod 262, the piston 264, the end cap 330, the flowdisc 338, and the end spool 354 can be manufactured from a variety ofmaterials and by numerous techniques. For instance, the end cap 330, theflow disc 338, and the end spool 354 can be cast from non-corrodingmetal or injection molded from plastic. The rod 262 and the piston 264can be made from a plastic or metal coated with a friction reducingmaterials, such as polytetrafluoroethlyene under the trademark Teflonsold by DuPont. In addition, given the benefit of this disclosure, oneskilled in the art will appreciate that the various components can bemodified (e.g., integrated with each other), yet the modified structuresremain within the scope of the control valve assembly concept.

Given the benefit of this disclosure, one skilled in the art willappreciate that the cartridge cage 266 can include a single sleeve ormultiple disc-shaped segments that are not coupled to adjacent segments.For instance, the end cap 330, the flow discs 338, and the end spool 354can be integrally formed or abut (without coupling). In alternativeconstructions, the cartridge cage 266 can be eliminated, such as byintegrating the seals into the valve chamber 44 (e.g., o-rings seated inannular recesses formed in an interior surface of the valve chamber 44).

As the piston 264 is translated within the cartridge cage 266, contoursabout the exterior surface 328 of the piston 264 influence the availableflow area and, in conjunction with the manifold 98, establish or inhibitflow passageways through the valve body 38. As shown in FIG. 13A, thepiston 264 further defines several flow zones and surfaces between thetip end 310 and the base end 312. A tip flow zone 364 is near the tipend 310 and includes three stepped rings 366, 368, 370 of increasingdiameter (moving away from the tip end 310 along the piston axis 308). Askewed ring 372 having the shape of a conical frustum is adjacent to thefinal stepped ring 370. Adjusting the position of the stepped rings 366,368, 370 and skewed ring 372 relative to the internal seals 326 willalter the area and hence flow rate of fluid flowing between the tip flowzone 364 and the valve chamber 44. For instance, a larger annular gapbetween a particular stepped ring 366, 368, 370 and a particularinternal seal 326 will allow increased fluid flow through the annulargap, provided other factors remain constant.

A cylindrically shaped tip seal surface 374 extends from an edge of theskewed ring 372 toward an intermediate flow zone 376. The tip sealsurface 374 is sized to selectively engage at least one of the internalseals 326 when the piston 264 is seated within the valve chamber 44. Theintermediate flow zone 376 includes opposing beveled rims 378, 380 andtwo stepped rings 382, 384. Again, the relative position of the steppedrings 382, 384 can influence the flow of fluid through the intermediateflow zone 376.

A cylindrically shaped intermediate seal surface 386 extends between theintermediate flow zone 376 and a cylindrically shaped base flow zone388. Similarly to the tip seal surface 374, the intermediate sealsurface 386 is sized to selectively engage at least one of the internalseals 326 when the piston 264 is seated within the valve chamber 44.Continuing toward the base end 312 of the piston 264, the base flow zone388 includes opposing beveled rims 390, 392 bridged by several fingers394 that extend axially to couple the intermediate seal surface 386 anda base seal surface 396. The fingers 394 define circumferentially spacedgaps 398 that allow fluid to flow through the gaps 398 into an interiorchamber 400 defined within the piston 264 and along the piston axis 308.Again, the base seal surface 396 is further configured to selectivelyengage at least one of the internal seals 326 when the piston 264 isseated within the valve chamber 44.

While the specific operation of the piston 264 will be described inconnection with the control valve assembly 10, there are alternativeconfigurations available for the piston 264. Several alternativeembodiments are illustrated in FIGS. 13B, 13C, 13D, and 13E. FIG. 13Billustrates a second embodiment of a piston 402 defining a tip flow zone404 having a generally conical form factor that expands radially outwardfrom a tip end 406 toward a tip seal surface 408. The tip flow zone 404defines a first segment 404A with a first slope and a second segment404B with a second slope that is less than the first slope of the firstsegment 404A; thus, the initial and subsequent flow of fluid can bemetered. An intermediate flow zone 410 includes a beveled rim 412adjacent to a necked cylindrical portion 414. Another conical surface416 flares radially outward from the cylindrical portion 414 to anotherbeveled rim 418 having a lesser slope than that defined by the conicalsurface 416. The beveled rim 418 is adjacent to a cylindricalintermediate seal surface 420, and the balance of the piston 402 issimilar to the piston 264 shown in FIG. 13A.

FIG. 13C illustrates a third embodiment of a piston 422 with a tip flowzone 424 similar to that shown in FIG. 13C. The tip flow zone 424 of thepiston 422, however, defines a conical form factor with a generallyuniform slope. An intermediate flow zone 426 is similar to the steppedversion shown in FIG. 13A. A fourth embodiment of a piston 428 is shownin FIG. 13D and includes a tip flow zone 430 that incorporates a seriesof geometric openings 432 circumferentially spaced about the piston 428near a tip end 434 of the piston 428. As shown in FIG. 13D, thegeometric openings 432 are in the form of an equilateral triangle havinga peak 436 proximate to the tip end 434 and a base 440 orientedperpendicular to a piston axis 442 of the piston 428. An intermediateflow zone 444 is similar to the piston 402 shown in FIG. 13B.

FIG. 13E illustrates a fifth embodiment of a piston 446 having ageometric opening 447 in a tip flow zone 450 oriented so that a base 452of the geometric opening 447 (e.g., in the form of a triangle) isproximate a tip end 455 and perpendicular to the orientation of a pistonaxis 456. An intermediate flow zone 458 is similar to the piston 264shown in FIG. 13A.

Returning to the overall operation of the control valve assembly 10, thevalve 180 can be manipulated to adjust the internal passagewaysavailable through the manifold 98 defined within the valve body 38. Theposition of the piston 264 within the valve chamber 44 adjusts thecontrol valve assembly 10 in to or out of an off position (as shown inFIGS. 14 and 15), a service position (as shown in FIGS. 16 and 17), ablend position (as shown in FIGS. 18 and 19), and a drain position (asshown in FIGS. 20 and 21). In addition to directing the flow of fluidthrough the manifold 98, the control valve assembly 10 can furtherinfluence the flow rate of fluid, such as by controlling the size of thepassageway through which the fluid flows (e.g., an annular space betweenthe piston 264 and the internal seals 326). The various operationalmodes of the control valve assembly 10 are described below withreference to FIGS. 14-22. In FIGS. 14-21, the flow of fluid in eachposition is generally illustrated with flow arrows and the manual bypassbody 50 is not shown in the drawings for clarity.

As shown in FIGS. 14 and 15, the control valve assembly 10 is in an offposition at which the valve 180 is configured to inhibit fluidcommunication between the supply port 46 and the service port 48.Specifically, fluid (e.g., treated fluid) flowing from the treatmentoutlet port 20 of the capacitive deionization device 12 into the inletport 42 of the valve body 38 is inhibited from flowing into the valvechamber 44, and thus through the valve chamber 44 into the service port48. When the point of entry is coupled to the control valve assembly 10and is configured to provide a supply fluid to the manifold 98 of thecontrol valve assembly 10, the supply fluid is directed to the supplyport 46 and into a supply passageway 460 of the manifold 98. The supplyconductivity sensor 82 secured to the valve body 38 extends into thesupply passageway 460 and provides a conductivity parameter to acontroller that is indicative of the fluid conductivity within thesupply passageway 460. The supply passageway 460 includes arcuate walls463 that curve toward the valve chamber 44. The supply passageway 460further includes an opening 465 through the valve body 38 into which thesupply pressure sensor 86 extends and provides a pressure parameter to acontroller that is indicative of a pressure of the supply fluid.

As also shown in FIGS. 14 and 15, the base seal surface 396 of thepiston 264 is configured to seal with the internal seals 326D, 326Ecaptured in the cartridge cage 266, in order to inhibit the supply fluidwithin the supply passageway 460 from entering the valve chamber 44. Thesupply passageway 460 establishes a ring-shaped portion 462 about thebase seal surface 396 into and through which the supply fluid can flow.With the valve 180 in the off position, supply fluid within the supplypassageway 460 can flow out of the manifold 98 through the generallyoval outlet port 40, and between the inner tube 32 and the outer tube 34into the treatment inlet port 18 of the capacitive deionization device12.

Any fluid (e.g., treated fluid) within the capacitive deionizationdevice 12 is also inhibited from flowing into the valve chamber 44.Specifically, treated fluid entering the manifold 98 through the inletport 42, which is in fluid communication with the treatment outlet port20 via the inner tube 32, flows into a treated passageway 464. Thetreated passageway 464 establishes a ring-shaped portion 466 about thetip seal surface 374 and the intermediate seal surface 386. The tip sealsurface 374 and the intermediate seal surface 386 are engaged byrespective internal seals 326A, 326B to inhibit treated fluid fromentering the valve chamber 44.

A drain passageway 448 is also formed within the manifold 98 and extendsfrom a drain port 449 (as best shown in FIGS. 2 and 4) to the valvechamber 44. The drain passageway 448 establishes a ring-shaped portion451 about the intermediate seal surface 386. The intermediate sealsurface 386 of the piston 264 seals against the internal seals 326B,326C to inhibit fluid from flowing between the valve chamber 44 and thedrain passageway 448.

Lastly, any fluid within a service passageway 454, which is in fluidcommunication with the service port 48, is allowed to flow into thevalve chamber 44 through the interior chamber 400. The fluid can flowthrough the gaps 398 and past the base end 312 of the piston 264. Fluidflowing through the gaps 398 is directed into an annular compartment 457that is defined and sealed by external seals 322C, 322D engaged againstthe valve chamber 44, and internal seal 326C engaged against theintermediate seal surface 386 and internal seal 326D engaged against thebase seal surface 396. Fluid flowing past the base end 312 is inhibitedfrom flowing out of the valve chamber 44 by the internal seal 326E, theexternal seal 322E, the o-ring 304, and the o-ring 294. Therefore, whenthe valve 180 is in the off position, fluid (e.g., supply fluid, treatedfluid, blended fluid) is inhibited from flowing through the manifold 98and being urged from the service port 48. The check valve 174 furtherinhibits fluid from flowing into the manifold 98.

If the valve 180 is not in the off position, the electric motor 176 canbe actuated by, for instance, a controller to drive the valve 180 to theoff position via the gear train 178. Specifically, the rotation of thepositioning gear 232 will cause translation of the longitudinal drivegear 242 to the off position illustrated in FIGS. 14 and 15. Theactuation of the electric motor 176 is orchestrated by the controller.For instance, the controller can monitor a magnet embedded in, orotherwise fixed to, the first stacked transfer gear 208, so that thecontroller can monitor rotation of the magnet to “count” the number ofrotations of the first stacked transfer gear 208. Given the known gearratios, each rotation of the first stacked transfer gear 208 correspondsto a linear movement of the longitudinal drive gear 242. In oneembodiment, full travel of the piston 264 corresponds to approximatelyone thousand rotations of the first stacked transfer gear 208,representing approximately one thousand pulses monitored by thecontroller.

As shown in FIG. 12, the control valve assembly 10 is configured so thatan axial end face 467 of the longitudinal drive gear 242 engages a stopsurface 470 formed in a cylindrical cavity 472 of the mounting plate186. The engagement between the stop surface 470 and the axial end face467 ultimately limits translation of the coupled piston 264, thus notimparting any additional stresses on the piston 264 when positioned inthe off position.

As shown in FIGS. 16 and 17, the control valve assembly 10 isillustrated in a service position, at which the valve 180 is configuredto direct supply fluid flowing into the supply port 46 into thecapacitive deionization device 12 and to direct treated fluid flowingfrom the capacitive deionization device 12 out of the service port 48.In one embodiment, the control valve assembly 10 provides fluidcommunication through the manifold 98 to direct supply fluid in thesupply port 46 through the supply passageway 460 and into the outletport 40 that is in fluid communication with the treatment inlet port 18.Treated fluid is also directed from the treatment outlet port 20 intothe inlet port 42, through the treated passageway 464 into the valvechamber 44, from the valve chamber 44 into the service passageway 454,and ultimately out of the service port 48 to a point of use.

Similar to when the control valve assembly 10 is in the off position,the service position directs supply fluid into the supply passageway 460of the manifold 98 where the base seal surface 396 of the piston 264remains in sealing engagement with the internal seals 326D, 326E, inorder to inhibit the supply fluid within the supply passageway 460 fromentering the valve chamber 44. Supply fluid within the supply passageway460 flows out of the manifold 98 through the outlet port 40 and into thetreatment inlet port 18 of the capacitive deionization device 12. Whilethe relative position of the piston 264 has slid rightward (as shown inFIG. 16), flow from the valve chamber 44 through the drain passageway448 also remains restricted as the intermediate seal surface 386 of thepiston 264 seals against the internal seal 326C and the tip seal surface374 seals against the internal seal 326B, in order to inhibit fluid fromflowing between the valve chamber 44 and the drain passageway 448.

As the piston 264 is slid along the valve axis 260 within the valvechamber 44, the contoured tip flow zone 364 will be gradually positionedadjacent to the internal seal 326A). Treated fluid will begin to flowthrough the treated passageway 464, between the internal seal 326A) andthe tip flow zone 364, into the valve chamber 44, and along the servicepassageway 454. The skewed ring 372 of the tip flow zone 364 can bepositioned relative to the internal seal 326A) to meter the flow oftreated fluid. Similarly, the stepped rings 366, 368, 370 of varyingdiameter can also be positioned relative to the internal seal 326A) toachieve the desired flow rate as the available fluid flow area isadjusted.

Similar to the configuration described when the control valve assembly10 is in the off position, fluid within the service passageway 454 isallowed to flow into the valve chamber 44 through the interior chamber400. The fluid can flow through the gaps 398 and past the base end 312of the piston 264, but remains sealed in the annular compartment 457 andthe valve chamber 44.

The service conductivity sensor 84 secured to the valve body 38 extendsinto the service passageway 454 and provides a conductivity parameter toa controller that is indicative of the fluid conductivity within theservice passageway 454. The service passageway 454 further includes anopening 474 through the valve body 38 into which the service pressuresensor 88 extends (as discussed above) and provides a pressure parameterto a controller that is indicative of a pressure of the treated fluid(when the control valve assembly 10 is in the service position).

Again, the positioning of the valve 180 is accomplished via a controlleractuating the electric motor 176, which in turn drives the gear train178 coupled to the positioning gear 232 resulting in translation of thelongitudinal drive gear 242 and the coupled piston 264. In one form, acontroller can monitor a flow rate parameter provided by the flow meter164 and adjust the position of the valve 180 to achieve a desired flowrate. In other forms, a controller can monitor and compare a supplypressure parameter and a service pressure parameter, and adjust theposition of the valve 180 to maintain a desired pressure differential.In other forms, the service conductivity sensor 84 can be monitored, sothat when the properties of the service fluid exceed a predeterminedthreshold, the valve 180 can be positioned in the blend position to mixsupply fluid with the service fluid thereby adjusting the properties ofthe blended fluid within a preferred range.

As shown in FIGS. 18 and 19, the control valve assembly 10 is in a blendposition at which the valve 180 is configured to direct a portion of thesupply fluid flowing into the supply port 46 toward the capacitivedeionization device 12, to direct treated fluid flowing from thecapacitive deionization device 12 out of the service port 48, and todirect a portion of the supply fluid to bypass the capacitivedeionization device 12 and into the service port 48. In one embodiment,the control valve assembly 10 provides fluid communication through themanifold 98 to direct supply fluid in the supply port 46 through thesupply passageway 460 and into the outlet port 40 that is in fluidcommunication with the treatment inlet port 18. Treated fluid is alsodirected from the treatment outlet port 20 into the inlet port 42,through the treated passageway 464, into the valve chamber 44, from thevalve chamber 44 into the service passageway 454, and ultimately out ofthe service port 48 to a point of use. These two flow paths are similarto those established when the control valve assembly 10 is in theservice position. The blend position defines an additional flow paththat allows the supply fluid and the treated fluid to mix in variousratios to establish a blended fluid that flows from the service port 48.

In the blend position, the piston 264 is slid further rightward from theservice position shown in FIGS. 16 and 17. As the piston 264 approachesthe blend position, the base flow zone 388 moves adjacent to theinternal seal 326D), ultimately providing fluid communication betweenthe ring-shaped portion 462 of the supply passageway 460 and the valvechamber 44 through which the supply fluid can flow. Specifically, thesupply fluid flows through the gaps 398 into the interior chamber 400defined within the piston 264. The supply fluid then can flow along theinterior chamber 400 toward the service passageway 454 where the supplyfluid ultimately mixes with treated fluid entering the valve chamber 44via the treated passageway 464.

In the control valve assembly 10, a controller can receive and useparameters from the supply pressure sensor 86, the supply conductivitysensor 82, the service pressure sensor 88, and the service conductivitysensor 84 to determine the desired position of the valve 180 required tomaintain the blended fluid within, for instance, a range ofconductivity. As another embodiment, the service pressure sensor 88 canprovide a service pressure parameter that indicates a fluid pressure inthe service passageway 454 that is at or below a minimum threshold. Inresponse, the controller can determine that the service fluid demandsrequire an increase in fluid pressure and flow. Thus, moving the valve180 to the blend position will allow additional supply fluid to, atleast temporarily, meet the service demands placed on the control valveassembly 10. Once the increased demand has been met (e.g., pressure inthe service passageway 454 exceeds a threshold), the valve 180 can bepositioned in the service position or the drain position (discussedbelow) to allow, for instance, regeneration of the capacitivedeionization device 12.

In the blend position, fluid remains inhibited from flowing from thevalve chamber 44 into the drain passageway 448. Specifically, the tipseal surface 374 abuts with the internal seal 326B and the intermediateseal surface 386 abuts with the internal seal 326C.

FIGS. 20, 21, and 22 illustrate the control valve assembly 10 in a drainposition. The drain position can be implemented to achieve a variety offunctions, such as cleaning the manifold 98 and/or the fluid treatmentdevice 12, regeneration of the fluid treatment device 12, and/ordirecting waste from the manifold 98 and/or the fluid treatment device12. In the control valve assembly 10, the piston 264 is positioned todirect supply fluid into the capacitive deionization device 12 via thecommunication between the outlet port 40 in the valve body 38 and thetreatment inlet port 18 in the capacitive deionization device 12,similar to the configuration illustrated for the off position. However,as shown in FIG. 22, the piston 264 has been slid or translated togenerally position the intermediate flow zone 376 of the piston 264adjacent to the internal seal 326B). As a result, fluid exiting thecapacitive deionization device 12 and entering the manifold 98 via theinlet port 42 flows through the treated passageway 464 (even though thefluid may be waste fluid) where it is directed into and through theintermediate flow zone 376 toward the drain passageway 448. The relativepositioning of the intermediate flow zone 376, and specifically theopposing beveled rims 378, 380 and the stepped rings 382, 384, can bealtered to adjust the flow rate of fluid between the treated passageway464 and the drain passageway 448.

The drain position, in addition to being usable during regeneration ofthe capacitive deionization device 12 or other water treatment device(e.g., a filter having a filter media), is also useable for cleaning anddraining purposes. In some forms, the flow rate is adjusted to be abovea minimum level required to prevent scaling and at or below a maximumlevel required to achieve the desired function (e.g.,regeneration—flowing more fluid than required to regenerate thecapacitive deionization device 12 is an inefficient use of fluid, whichis preferably avoided).

FIGS. 23-29 illustrate one alternative control valve assembly 476. Asshown in FIGS. 23 and 24, the control valve assembly 476 includes agenerally cubic valve body 478 defining a series of ports, including asupply port 480, a drain port 482, a service port 484, an outlet port486, and an inlet port 488. A point of entry providing a supply fluidcan be coupled in fluid communication with the supply port 480 and apoint of use can be coupled in fluid communication with the service port484. Also, the outlet port 486 and the inlet port 488 can be configuredin fluid communication with respective inlet and outlet ports of a watertreatment device (e.g., a capacitive deionization device). The controlvalve assembly 476 is configured to provide selective fluidcommunication to direct fluid (e.g., supply fluid, treated fluid,blended fluid, drain fluid) between desired ports and to establishmulti-port blending.

A valve chamber 490 is formed within the valve body 478 to house a valve492. The valve 492 includes a piston 494 slidably seated within acartridge cage 496, which is seated within the valve chamber 490. Thecartridge cage 496 further includes external seals 498 in engagementwith the valve chamber 490 and internal seals 500 in engagement with thepiston 494. As the piston 494 slides along a valve axis 502 within thevalve chamber 490, the internal seals 500 wipe against the piston 494 toestablish various flow passageways through a manifold 504 defined withinthe valve body 478. The piston 494 can be moved between variouspositions by a similar arrangement described above with reference to thepiston 264 or by any other appropriate construction.

FIG. 25 illustrates the alternative control valve assembly 476 in an offposition at which fluid entering the inlet port 488 is inhibited fromflowing out of the service port 484. Specifically, a supply fluid entersthe supply port 480 and flows through a supply passageway 506 toward thevalve chamber 490. The internal seals 500D, 500E seal against a baseseal surface 508 of the piston 494 to inhibit supply fluid from enteringthe valve chamber 490. The supply fluid also flows along an elongatedoutlet passageway 510 to the coupled fluid treatment device. Fluid canenter the manifold 504 via the inlet port 488 where if flows along aninlet passageway 512 toward the valve chamber 490. However, sealingengagement between the internal seal 500A and a tip seal surface 514,and between the internal seal 500C and an internal seal surface 524directs the fluid toward the drain port 482. Fluid within a servicepassageway 516 can flow through gaps 518 in a base flow zone 520 into afluid receptacle 522, which is defined by internal seals 500C, 500Dengaged with the internal seal surface 524 and the base seal surface508, respectively. Fluid flowing toward a base end 526 of the piston 494can be contained in a similar manner described with reference to thecontrol valve assembly 10.

FIG. 26 illustrates the control valve assembly 476 in a service positionat which supply fluid is in fluid communication with the fluid treatmentdevice and treated fluid is in fluid communication with the service port484. Specifically, supply fluid is directed as described when thecontrol valve assembly 476 is in the off position, but the piston 494 ismoved to the position shown in FIG. 26. In the service position, treatedfluid entering the inlet port 488 flows through the inlet passageway 512to the valve chamber 490. The treated fluid then flows along a tip flowzone 528 between the piston 494 and the internal seal 500A into theservice passageway 516. The tip flow zone 528 includes tapered steps 530that transition to a necked portion 532 that can be positioned to adjustthe flow rate of fluid passing through the tip flow zone 528. The neckedportion 532 is adjacent to a beveled rim 534 that flares radiallyoutward toward a bypass seal surface 536 (describe below). Internal seal500B seals against the tip seal surface 514 to inhibit fluid fromflowing along a drain passageway 538 to the drain port 482. Fluidflowing through the gaps 518 in the base flow zone 520 continues to bedirected into the fluid receptacle 522.

FIG. 27 illustrates the control valve assembly 476 in a blend positionat which a blended fluid is directed from the service port 484. Thepiston 494 directs the supply fluid both through the outlet passageway510 for treatment by the fluid treatment device and through the valvechamber 490 where it is mixed with treated water flowing through theinlet passageway 512. Specifically, supply fluid is directed through thegaps 518 in the base flow zone 520 toward the service passageway 516.Supply fluid is also directed along the outlet passageway 510, throughthe outlet port 486, and in to the fluid treatment device. Treated fluidfrom the fluid treatment device enters the valve body 478 via the inletport 488 and flows along the inlet passageway 512 toward the valvechamber 490. In the blend position, the tip flow zone 528, specificallythe necked portion 532, is positioned to extend across the internal seal500A so that treated fluid can flow between the internal seal 500A andthe necked portion 532 toward the service passageway 516. The treatedfluid and the supply fluid mix to establish a blended fluid that then isdirected from the service port 484.

The control valve assembly 476 further includes a bypass position (asshown in FIG. 28) at which supply fluid is directed from the supply port480, through the valve chamber 490, and from the service port 484,without mixing with treated fluid provided by a fluid treatment device.The piston 494 is positioned so that the base flow zone 520 is adjacentto the supply passageway 506. Supply fluid flows through the gaps 518and along the valve axis 502 toward the service passageway 516. Supplyfluid can flow through the outlet passageway 510, however, internalseals 500A, 500B engage the bypass seal surface 536 and the tip sealsurface 514, respectively, to inhibit treated fluid from entering theservice passageway 516. As a result, the supply fluid bypasses the fluidtreatment device and is directed downstream to the service port 484.

Similar to the control valve assembly 10, the control valve assembly 476includes a drain position, as shown in FIG. 29. In the drain position,the control valve assembly 476 directs supply fluid though the outletpassageway 510 and directs fluid in the inlet passageway 512 through thevalve chamber 490, to the drain passageway 538, and ultimately out ofthe drain port 482. Specifically, fluid enters the inlet port 488 andflows along the inlet passageway 512 to the valve chamber 490. Thepiston 494 is slid within the valve chamber 490 to the position shown inFIG. 29 to align an intermediate flow zone 542 and the internal seal500B. The alignment results in fluid flowing between the piston 494 andthe internal seal 500B toward the drain passageway 538 (as shown in FIG.24). The intermediate flow zone 542 further includes stepped rings 544,546 that can be positioned relative to the internal seal 500B to meteror adjust the flow of fluid as the size and form of the opening isaltered.

Operation of the control valve assembly concept (e.g., adjusting theposition of the valve) can be partially or completely automated. FIG. 30illustrates a control valve assembly 548 in communication with acontroller 550 to control the movement of the control valve assembly 548between various positions (e.g., an off position, a service position, ablend position, a bypass position, a drain position, etc.). While thecontroller 550 can operate without receiving parameters from sensors(e.g., such as by adjusting the position based on timers, temporalschedules, direct input from a user, etc.), the controller 550 isillustrated as being in communication with a supply sensor 552, aservice sensor 554, and a system sensor 556.

The controller 550 is configured to adjust (e.g., translate) the controlvalve assembly 548 to direct fluid from and between a point of entry558, a fluid treatment device 560, a point of use 562, and a drain 564.In particular, the control valve assembly 548 includes a supply port 566in fluid communication with the point of entry 558, an outlet port 568in fluid communication with a treatment inlet port 570, an inlet port572 in fluid communication with a treatment outlet port 574, a serviceport 576 in fluid communication with the point of use 562, and a drainport 578 in communication with the drain 564. As one example adjustment,when the control valve assembly 548 is in the off position, thecontroller 550 can monitor the service sensor 554 (e.g., a pressuresensor) so that when the service pressure is below a minimum level(indicating that a demand for fluid exists), the controller 550 canadjust the control valve assembly 548 from the off position to theservice position.

In one embodiment, the controller 550 can monitor the system sensor 556for a parameter indicative of the fluid level or pressure in a treatedwater storage tank. If the controller 550 determines that the demand fortreated water (as indicated by a low fluid level or low pressure withinthe treated water storage tank) exceeds the throughput capacity of thefluid treatment device 560, the controller 550 can adjust the valve tothe blend position. Specifically, a motor can be operatively coupled tothe valve and the controller 550. The controller 550 communicates withthe motor to energize the motor and thus adjust the control valveassembly 548 to the blend position, or a particular position within arange of blend positions depending on the calculated fluid demand. Inthe blend position, both the supply fluid and the treated fluid aredirected through the service port 576 so that a blended fluid(comprising the supply fluid and the treated fluid) is directed from thevalve body to the point of use 562, either directly or indirectly via atreated water storage tank.

If the controller 550 determines that the blend position is stillinsufficient to meet or maintain current fluid demands, the controller550 can adjust the control valve assembly 548 to the bypass position, sothat supply fluid is routed from the supply port 566 to the service port576, without being inhibited by the limited throughput of the fluidtreatment device 560. Fluid communication with the fluid treatmentdevice 560 can be restored, for instance, when the service sensor 554(e.g., a flow meter) monitored by the controller 550 indicates a reduceddemand that will allow the fluid treatment device 560 to again treat atleast a portion of the supply fluid entering the control valve assembly548.

Alternatively, the service sensor 554 can include a conductivity sensorproviding a parameter indicative of the conductivity of the fluidflowing through the service port 576. If the controller 550 monitoringthe service sensor 554 determines that the conductivity of the servicefluid is outside of an acceptable range, the controller 550 can actuatethe control valve assembly 548 to the blend position or the serviceposition, in order to maintain the integrity of the service fluid at theexpense of decreased fluid throughput. In another example, if thecontroller 550 monitoring the service sensor 554 determines that theconductivity of the service fluid is outside of an acceptable range, thecontroller 550 can determine that regeneration of the fluid treatmentdevice 560 is required and move the control valve assembly 548 to thedrain position.

In some embodiments, when the control valve assembly 548 is in the blendposition, the supply sensor 552 connected to the controller 550communicates a supply parameter to the controller 550, and the servicesensor 554, which is also connected to the controller 550, communicatesa service parameter to the controller 550. The controller 550 isconfigured to monitor the supply parameter and the service parameter ofthe blended fluid, and to determine or calculate a difference betweenthe supply parameter and the service parameter. The difference is thencompared to a threshold or desired level and the position of the controlvalve assembly 548 is adjusted to alter the blend position accordinglyto target the threshold. In some forms, this logic can define a controlloop carried out by the controller 550 as a technique to monitor andmaintain the properties of the fluid exiting the control valve assembly548 at a threshold, a level, or within a range.

The controller 550 can be configured to communicate with a variety ofsensor types. For instance, the supply sensor 552, the service sensor554, and the system sensor 556 can include one or more of the followingtypes of sensors: a system temperature sensor (e.g., to sense theambient temperature), a system pressure sensor (e.g., to sense thepressure within a system storage tank), a system fluid volume sensor(e.g., to sense the fluid volume or level within a system storage tank),a fluid temperature sensor (e.g., to sense the temperature of the supplyfluid), a flow sensor (e.g., to sense the flow rate of fluid entering orexiting the control valve assembly 548), a flow pressure sensor (e.g.,to sense the pressure of the fluid entering or exiting the control valveassembly 548), a conductivity sensor (e.g., to sense the conductivity ofthe fluid flowing through the control valve assembly 548), and a pHsensor (e.g., to sense the pH of the fluid flowing through the controlvalve assembly 548).

In some embodiments, the controller 550 can monitor the sensors andadjust the position of the control valve assembly 548 in response to thesensed parameters. For instance, the controller 550 can monitor anambient temperature sensor and adjust the control valve assembly 548from an off position to a drain position if the ambient temperatureexceeds a threshold, in order to use the supply fluid as a heat sink toextract heat from the control valve assembly 548 and/or the fluidtreatment device 560. In other embodiments, the controller 550 canmonitor a temperature of the supply fluid and adjust the control valveassembly 548 if the temperature of the supply fluid exceeds a threshold,in order to prevent supply fluid having an excessive temperature fromflowing through the fluid treatment device 560 and potentially damagingthe fluid treatment device 560. In yet other embodiments, the controller550 can monitor a flow meter for a parameter indicative of slow supplyfluid flow or fast service fluid flow, and adjust the position of thecontrol valve assembly 548 to direct additional fluid through thecontrol valve assembly 548 as needed. The parameter can also beindicative of a no flow condition, at which power to the fluid treatmentdevice 560 can be reduced or turned off until fluid demand is againindicated.

FIG. 31 shows a simplified schematic of another embodiment of a controlvalve assembly 600. A controller 602 is in communication with a sensor604, a motor 606, and an energy reserve 608. The motor 606 is coupled toa valve 610 that is seated within a valve body 612. Energizing the motor606 can selectively move the valve 610 between an operating position anda fault position. In the operating position, the control valve assembly600 can be in, for instance, the service position, the blend position,the bypass position, or the drain position discussed above. Similarly,depending on the application requirements, the fault position can be,for instance, the off position, the service position, the blendposition, the bypass position, or the drain position. The position ofthe valve 610 that is associated with the operating position and theservice position can be selected depending on, for instance, the type ofwater treatment system the control valve assembly 600 is coupled toand/or the type of fault condition encountered by the control valveassembly 600.

The energy reserve 608 is shown operationally coupled to the controller602, the sensor 604, and the motor 606. As a result, the energy reserve608 can provide energy to operate the coupled devices if the controlvalve assembly 600 experiences a fault condition in the form of a lineenergy loss (e.g., line power to the controller 602 is interruptedtemporarily or for an extended period). The energy reserve 608 caninclude various energy storage devices, such as a battery or a capacitorthat are of sufficient capacity (e.g., amp-hours) to power at least oneof the controller 602, the motor 606, and the sensor 604 to move thevalve 610 to the desired fault position after a loss of line energy.

The sensor 604 can be any suitable type of sensor (e.g., a line energysensor, a valve position sensor, a temperature sensor, a flow sensor, acurrent sensor, a pressure sensor, etc.) that senses some property 614of the control valve assembly 600 or the overall water treatment systemthat the control valve assembly 600 is integrated into. The controller602 monitors the sensor 604 to receive a fault signal from the sensor604 that indicates a fault condition of the control valve assembly 600or the overall water treatment system. In response to the fault signal,the controller 602 can energize the motor 606 (e.g., an electric motoror a hydraulically actuated motor) to drive the valve 610 to the faultposition.

In one embodiment, the sensor 604 can be a conductivity sensor thatprovides a fault signal when the conductivity sensor fails tocommunicate (or indicates a fault in the conductivity sensor). Thecontroller 602, in response to the fault signal, actuates the motor 606to drive the valve 610 to the blend position (i.e., one type of faultposition), and can also indicate (e.g., via a display, audible tone,etc.) that a fault of the control valve assembly 600 has occurred. Inthe blend position, a blended fluid including the supply fluid and thetreated fluid is directed from the valve body 612 to the point of use.

In another embodiment, the sensor 604 can include a line energy sensorthat provides a fault signal indicative of a loss of line energy to thecontrol valve assembly 600. The energy reserve 608 can be electricallyintegrated to provide near continuous (i.e., substantiallyuninterrupted) power to the controller 602, the sensor 604, and themotor 606. In response to the fault signal, the controller 602 cancontrol the motor 606 to drive the valve 610 to the fault position, suchas a bypass position, by drawing on power supplied by the energy reserve608. When line energy to the control valve assembly 600 is interrupted,the control valve assembly 600 can be moved to the bypass position viaenergy provided by the energy reserve 608, so that fluid can passthrough the control valve assembly 600 to the point of use even if thecontrol valve assembly 600 is without line power.

While FIG. 31 schematically shows the energy reserve 608 and the sensor604 as separate from the controller 602, one or both can be integralwith the controller 602. In one embodiment, the energy reserve 608 isintegral with the controller 602 (e.g., an on-board capacitor orbattery). Other embodiments of the control valve assembly 600 include amotor having a sensor (e.g., a Hall effect sensor) that is incommunication with the controller 602 and also operationally coupled tothe energy reserve 608. The controller 602 can monitor the sensor toadjust the position of the valve 610 from an operating position to thedesired fault position, even in situations of line energy loss.

FIG. 32 is a flow chart showing an example fault control loop executedby the controller 602. The controller 602 monitors the sensor 604 atStep 616 for a fault signal indicating a fault condition (e.g., excessmotor temperature, line energy loss, no fluid flow, etc.). If no faultcondition is identified at Step 618, the controller 602 returns tomonitoring the sensor 604 for a fault signal at Step 616. If a faultcondition is identified at Step 618, the controller 602 moves the valve610 to the fault position at Step 620. The fault position can bepredetermined or selected in accordance with logic that factors thespecific type of water treatment device and the instant fault condition.The controller 602 can adjust the position of the valve 610 byenergizing the motor 606 to drive the valve 610 from the operatingposition to the appropriate fault position.

At Step 622, the controller 602 continues to monitor the sensor 604 todetermine if the fault condition has been corrected. If the faultcondition remains, the valve 610 is maintained in the fault position. Ifthe fault condition was indicative of a loss of line energy, thecontroller 602 can be configured to shut down once the valve 610 is inthe fault position (e.g., the bypass position). If the fault conditionhas been corrected, the controller 602 can be configured to move thevalve 610 to the operating position at Step 624. The controller 602 thenresumes monitoring the sensor 604 at Step 616. The fault condition mayalso be remedied with user interaction. For instance, the controller 602can include a display that provides information regarding the faultcondition and an input device that requires that a user acknowledge ortake additional action to remedy the fault before the controller 602resumes operation of the control valve assembly 600.

In some embodiments, the controller 602 can compare a current positionof the valve 610 to the desired fault position (e.g., a blend position)and adjust the position of the valve 610 from the current position tothe fault position. The controller 602 can monitor the current positionof the valve 610 using various techniques, including a magnetic pickupwith pulses corresponding to linear movement of the valve 610, opticalsensors, and other position sensors.

The controller 602 can also include application-specific logic that istailored to the type of system (e.g., electrochemical deionizationdevice, capacitive deionization device, water softener, water filter,etc.) that the control valve assembly 600 is in communication with. Forinstance, if the system includes an electrochemical deionization deviceand the fault condition indicates a line energy loss, the controller 602can control the motor 606 to move the valve 610 to the bypass positionto allow supply fluid to flow uninhibited through the control valveassembly 600 to the point of use. Alternatively, if the system includesa water filter, the controller 602 can control the motor 606 to move thevalve 610 to a service position when a jammed valve 610 fault conditionis indicated in order to maintain some level of filtration.

The sensor 604 can be monitoring a variety of aspects of the overallwater treatment system. For instance, the sensor 604 can include a flowmeter within the valve body 612, at the point of entry, or at the pointof use that can be monitored by the controller 602 to determine if thereis an unexpected flow of fluid (e.g., flow to the point of use when thevalve 610 is in the off position). In another embodiment, the controller602 may include a timer that monitors the elapsed time to move the valve610 a full stroke or cycle. This elapsed time can be compared to apredetermined or a typical elapsed time. If the monitored time exceedsthe expected time, a fault condition (e.g., indicative of abinding/jammed valve, a motor fault, etc.) can result in the controller602 moving the valve 610 to the associated fault position (e.g., the offposition) where the control valve assembly 600 can be serviced.

In other embodiments, the controller 602 can move the valve 610 to anominal position at the beginning of a cycle (e.g., at initial power upof the control valve assembly 600, after a drain cycle, etc.). Thecontroller 602 can then move the valve 610 to a first position whilemonitoring the sensor 604. For instance, the controller 602 may monitora flow meter and control the motor 606 to drive the valve from an offposition to a service position. If the controller 602 receives a faultsignal from the flow meter (e.g., a no-flow signal), despite thepresumed movement of the valve 610 into the service position, thecontroller 602 can move the valve 610 to a fault position (e.g., an offposition). The communication between the controller 602 and the sensor604 allows the control valve assembly 600 to establish the desiredoperating conditions and provides a point of reference to allow thevalve 610 to be positioned for flow control, which benefits fromaccurate positioning. The controller 602 can also be programmed torecalibrate the position of the valve 610 at specific times or intervals(e.g., number of cycles, point in cycle, etc.).

In some alternative embodiments a control valve assembly can incorporatemultiple valves, with one valve being adjusted to direct the flow offluid and another valve being adjusted to influence the flow rate of thefluid. FIG. 33 illustrates an alternative drive configuration. Aneccentric drive arrangement 900 includes a drive gear 902 that isengaged by, for example, an electric motor via a gear train 904. Thedrive gear 902 includes an eccentric mount 906 that protrudes from aside face 908 of the drive gear 902. The eccentric mount 906 is sized toslidably engage a slot 910 formed in a triangular yoke 912. A taperedend 914 of the yoke 912 is fixed coupled to an end 916 of a rod 918. Apiston 920 is engaged with an opposite end 922 of the rod 918.

The mechanics of the eccentric drive arrangement 900 cause translationof the piston 920 in response to rotation of the drive gear 902.Specifically, as the eccentric mount 906 on the drive gear 902 traversesa circular path relative to a stationary valve body 924, the yoke 912 istranslated along a valve axis 926 as the eccentric mount 906 oscillatesbetween ends 928, 930 of the slot 910. The translation of the yoke 912results in translation of the attached rod 918 and piston 920, allowingthe position of the piston 920 to be adjusted. Alternative motors canalso be incorporated into the control valve assembly concept. Forinstance, hydraulically actuated motors (e.g., chambers and bellows) canbe configured to move a piston of an alternative control valve assembly.

FIG. 34 shows an embodiment of a control valve assembly 800 mounted toan embodiment of a capacitive deionization device 802. Similar to thecontrol valve assembly 10, the control valve assembly 800 is in fluidcommunication with the capacitive deionization device 802. Thecapacitive deionization device 802 includes a vessel 804 that defines achamber 806. A series of flow-through capacitors 808 are seated withinthe chamber 806 on a floor 810 of the chamber 806. The series offlow-through capacitors 808 are compressed between the floor 810 and acompression element 812.

The flow-through capacitor 808 includes a stack of individual fluidprocessing cells. Each cell in the stack includes one or more of acombination of the following elements: electrode pairs, cationmembranes, anion membranes, and flow spacers, which are typically madeof a plastic mesh. While the cation and anion membranes may be used toprovide improved attachment and storage of the constituents on theelectrodes, the membranes are not required and the cells can bemanufactured without them. Additionally, the electrode may beconstructed to have a two-part electrode construction including a carbonadsorptive electrode layer and a current collector.

In the embodiment shown in FIG. 34, each of these cell elements is inthe form of a relatively thin layer (with a central opening) that isdisposed in parallel with the other layers and stacked upon one anotherin a repeating pattern of first electrode/cation membrane/spacer/anionmembrane/second electrode/anion membrane/spacer/cation membrane. Afterthe last cation membrane, there can be another first electrode and thepattern can be repeated. Since any flux of charged constituents occursas the result of a voltage difference created between the first and thesecond electrodes, electrode layers can form the bottommost and topmostlayers of the stack.

The flow-through capacitor 808 includes many electrode pairs. In oneembodiment, each electrode pair includes a first electrode (which duringtreatment acts as a cathode) and a second electrode (which duringtreatment acts as an anode). The electrodes may be constructed fromhigh-surface area electrically conducting materials such as, forexample, activated carbon, carbon black, carbon aerogels, carbonnanofibers, carbon nanotubes, graphite, graphene, or mixtures thereof.In some embodiments, the electrodes can be placed as a separate layer ontop of a current collector or can alternatively be coated directly ontothe current collector. The electrodes are configured and electricallyconnected relative to each other to establish a voltage difference orpotential there between. The first electrodes in the flow-throughcapacitor 808 can be connected to one another and are then connected toa power supply. Similarly, the second electrodes in the flow-throughcapacitor 808 can be connected to one another and are then connected tothe power supply. The electrodes can be connected to one another attheir outer edges using peripheral tabs that contact one another orusing other forms of connection. The stack can be arranged so thatnearest neighbor electrodes will be of different kinds (i.e., the firstelectrodes will be disposed between the second electrodes andvise-versa). In some embodiments, the various electrode sets may beinterleaved with one another and arranged so as to place multipleelectrode pairs in series with one another.

Regardless of the specific electrical arrangement and connectivity ofthe electrodes, during operation these first and second electrodes canbe differently charged from one another to establish a voltage potentialacross the electrodes pairs. This voltage potential can be used toeither draw charged constituents out of the fluid toward the electrodes(such as during treatment) or release the collected constituents backinto the fluid (such as during regeneration, discharge, or cleaning).Cation membranes and anion membranes are positioned adjacent to thefirst electrode and the second electrode, respectively. The cationmembrane and the anion membrane act as charge barriers that can beplaced between the electrodes and the centrally-disposed flow spacer.The term “charge barrier” as used herein refers to a layer of materialthat can hold an electric charge and that is permeable or semi-permeablefor ions. Ions with the same charge signs as that in the charge barriercannot pass through the charge barrier to the corresponding electrode.As a result, ions that are present in the electrode compartment adjacentto the charge barrier and that have the same charge sign as the chargein the charge barrier are at least temporarily retained or trapped inthe electrode compartment. A charge barrier may allow an increase in ionremoval efficiency as well as a reduction in the overall energyconsumption for ion removal.

The plastic mesh flow spacer is disposed between the cation membrane andthe anion membrane (and the corresponding electrode pair). This meshspacer has a pattern similar to a window screen and also has somesections that are thicker than others sections in the height dimension(the height dimension is generally perpendicular to the direction offlow through the spacers) so that, when the spacer layer is lightlycompressed between two other layers (e.g., the cation membrane and theanion membrane) fluid is able or permitted to flow across the spacerlayer and between the corresponding pairs of electrodes.

A flow-through capacitor will likely include tens or hundreds ofelectrode pairs to provide an appropriate amount of surface area fordeionization of a usable amount of treated fluid. Moreover, as shown inFIG. 34, multiple modules or trays of cell components can be constructedcontaining a number of electrode pairs that are stacked on one anotherand the trays separately or aggregately compressed. Additionally, thevarious layers of the stack are compressed to control the amount ofspace between the cell components, thereby establishing a cross-sectionarea through which the fluid can flow through the stack. Thiscompression may be done in a number of ways. In one embodiment, apressure plate (e.g., compression element 812) at the top of theflow-through capacitor can compress the cell components or layers in adirection perpendicular to the direction of fluid flow through thestack. A pressure plate can apply a variable compressive force bymechanical fastening (e.g., employing a threaded screw element which maybe tightened or loosened to adjust compressive force). In otherembodiments, the stack may be divided into multiple portions with eachportion being separately compressible.

The control valve assembly 800 shown in FIG. 34 includes a valve body814 with a collar 816 that is mounted on the vessel 804. An outlet port818 of the control valve assembly 800 is in fluid communication with atreatment inlet port 820 of the capacitive deionization device 802, andan inlet port 822 is in fluid communication with the treatment outletport 824 of the capacitive deionization device 802.

When the control valve assembly 800 is in the service position or theblend position, supply fluid flowing from the control valve assembly 800flows through the outlet port 818, into the treatment inlet port 820,and into the chamber 806 of the vessel 804. The supply fluid flowsradially inward through the flow-through capacitors 808 toward a centralcolumn 826. Treated fluid then flows along the central column 826 atoward passageway 828 formed through the compression element 812. Thepassageway 828 defines the treatment outlet port 824 that is in fluidcommunication with the inlet port 822 of the control valve assembly 800.Treated fluid flows into the inlet port 822 and is directed through thecontrol valve assembly 800 to the point of use. In some instances oroperational cycles, fluid can be directed through the flow-throughcapacitor 808 in a reverse direction. In some embodiments, to achieve adesired flow pattern within the flow-through capacitor 808, there can bemultiple water inlets or structures that promote an even or otherwisedesirable fluid flow pattern through the flow spacers in the stack.There can be additional structural elements that are used to position,electrically connect, and/or compress some or all of the cell elementsin the stack.

It will be appreciated by those skilled in the art that while theinvention has been described above in connection with particularembodiments and examples, the invention is not necessarily so limited,and that numerous other embodiments, examples, uses, modifications, anddepartures from the embodiments, examples, and uses are intended to beencompassed by the claims attached hereto. The entire disclosure of eachpatent and publication cited herein is incorporated by reference, as ifeach such patent or publication were individually incorporated byreference herein. Various features and advantages of the invention areset forth in the following claims.

The invention claimed is:
 1. A control valve assembly capable of beingin fluid communication with a point of entry providing a supply fluid, afluid treatment device defining a treatment inlet port for receiving thesupply fluid and a treatment outlet port for supplying a treated fluid,and a point of use, comprising: a valve body including a supply port influid communication with the point of entry to direct the supply fluidfrom the point of entry to the valve body; an outlet port in fluidcommunication with the treatment inlet port to direct the supply fluidfrom the valve body to the fluid treatment device; an inlet port influid communication with the treatment outlet port to direct the treatedfluid from the fluid treatment device to the valve body; and a serviceport in fluid communication with the point of use to direct at least oneof the supply fluid and the treated fluid from the valve body to thepoint of use; and a valve movable within the valve body and has a blendposition at which both the supply fluid and the treated fluid aredirected through the service port so that a blended fluid including thesupply fluid and the treated fluid is directed from the valve body tothe point of use.
 2. The control valve assembly of claim 1 and furthercomprising at least one of: a supply sensor seated in the valve bodyproximate to the supply port to sense a supply parameter of the supplyfluid; and a service sensor seated in the valve body proximate theservice port to sense a service parameter of at least one of the treatedfluid and the blended fluid.
 3. The control valve assembly of claim 2wherein: the supply sensor includes at least one of a supply temperaturesensor, a supply flow sensor, a supply pressure sensor, a supplyconductivity sensor, and a supply pH sensor; and the service sensorincludes at least one of a service temperature sensor, a service flowsensor, a service pressure sensor, a service conductivity sensor, and aservice pH sensor.
 4. The control valve assembly of claim 1 wherein: thevalve body includes a valve chamber; and the valve includes a cartridgecage seated in the valve chamber; a piston slidably seated in thecartridge cage to translate along a piston axis; and a rod coupled tothe piston and extending from the valve chamber.
 5. The control valveassembly of claim 4 and further comprising a motor engaged with the rodto translate the piston along the piston axis to the blend position. 6.The control valve assembly of claim 1 wherein: the valve includes acylindrical piston extending along a piston axis and defining anexterior surface between a base end and a tip end; and the exteriorsurface defines a reduced portion with a reduced diameter relative to anadjacent diameter of the exterior surface.
 7. The control valve assemblyof claim 1 wherein: the valve includes a piston extending along a pistonaxis between a base end and a tip end; and the base end includes aplurality of resilient arms; and further comprising a rod defining avalve end and a drive end, the valve end being captured by the resilientarms and the drive end extending from the valve body, and a longitudinaldrive gear being coupled to the drive end of the rod.
 8. The controlvalve assembly of claim 1 wherein a drive gear is coupled to the valveso that a movement of the drive gear relative to the valve bodytranslates the valve within the valve body.
 9. The control valveassembly of claim 8 wherein: the movement of the drive gear includestranslation of the drive gear; and the translation of the valve by thedrive gear is limited by engagement between an axial end face of thedrive gear and a stop surface of the valve body.
 10. The control valveassembly of claim 1 wherein the valve is movable to a bypass position atwhich the supply fluid is directed from the supply port to the serviceport and is inhibited from flowing into the treatment inlet port.
 11. Acontrol valve assembly capable of being in fluid communication with apoint of entry providing a supply fluid, a fluid treatment devicedefining a treatment inlet port for receiving the supply fluid and atreatment outlet port for supplying a treated fluid, and a point of use,comprising: a valve body including a supply port in fluid communicationwith the point of entry, an outlet port in fluid communication with thetreatment inlet port, an inlet port in fluid communication with thetreatment outlet port, and a service port in fluid communication withthe point of use; a manifold defined within the valve body and in fluidcommunication with the supply port, the outlet port, the inlet port, andthe service port; a valve chamber defined within the valve body; and avalve movably seated within the valve chamber and intersecting themanifold; the manifold including a supply passageway directing thesupply fluid from the supply port to the outlet port and the valvechamber, a treated passageway directing the treated fluid from the inletport to the valve chamber, and a service passageway directing at leastone of the supply fluid and the treated fluid from the valve chamber tothe service port; and the valve having a blend position at which ablended fluid is directed through the service passageway and includesthe supply fluid directed through the supply passageway and the treatedwater directed through the treated passageway.
 12. The control valveassembly of claim 11 and further comprising at least one of: a supplyconductivity sensor seated in the valve body proximate to the supplypassageway to sense a supply conductivity of the supply fluid; a serviceconductivity sensor seated in the valve body proximate the servicepassageway to sense a service conductivity of at least one of thetreated fluid and the blended fluid; a supply pressure sensor seated inthe valve body proximate to the supply passageway to sense a supplypressure of the supply fluid; and a service pressure sensor seated inthe valve body proximate the service passageway to sense a servicepressure of at least one of the treated fluid and the blended fluid. 13.The control valve assembly of claim 11 and further comprising: a motor;and wherein the valve includes a cartridge cage seated in the valvechamber, a piston slidably seated in the cartridge cage to translatealong a piston axis, and a rod coupled to the piston and extending fromthe valve chamber; and wherein the motor translates the rod and thepiston along the piston axis to the blend position.
 14. The controlvalve assembly of claim 11 wherein the valve is movable to an offposition at which the supply fluid is inhibited from flowing through thesupply passageway into the valve chamber.
 15. The control valve assemblyof claim 11 wherein the valve is movable to a service position at whichthe supply fluid flows through the supply passageway to the outlet portand is inhibited from flowing into the valve chamber, and the treatedfluid flows through the treated passageway and the service passageway tothe service port.
 16. The control valve assembly of claim 11 wherein thevalve is movable to a drain position at which the supply fluid flowsthrough the supply passageway to the outlet port and is inhibited fromflowing into the valve chamber, drain fluid flows from the inlet port tothe valve chamber and through a drain passageway establishing fluidcommunication between the valve chamber and a drain port.
 17. Thecontrol valve assembly of claim 11 wherein the fluid treatment device isa capacitive deionization device.
 18. An electrochemical deionizationsystem including an electrochemical deionization device between a pointof entry and a point of use, the system comprising: a valve body coupledto the electrochemical deionization device; and a valve movablypositioned inside the valve body, the valve having a first position inwhich treated fluid from the electrochemical deionization device issupplied to the point of use through the valve body and untreated fluidis simultaneously supplied from the point of entry to the point of usethrough the valve body in order to blend untreated fluid with treatedfluid.
 19. The system of claim 18 wherein the valve includes a secondposition in which untreated fluid from the point of entry is supplied tothe electrochemical deionization device.
 20. The system of claim 19wherein the valve includes a third position in which treated fluid fromthe electrochemical deionization device is supplied to the point of use.21. The system of claim 20 wherein the valve is moved to the firstposition due to increased demand for fluid at the point of use.
 22. Thesystem of claim 21 wherein the valve includes a fourth position in whichthe electrochemical deionization device is bypassed and untreated fluidis supplied from the point of entry to the point of use.
 23. The systemof claim 22 wherein the valve is moved to the fourth position due to aline energy loss.
 24. The system of claim 18 wherein the valve bodyincludes a supply port in fluid communication with the point of entryand a service port in fluid communication with the point of use.
 25. Thesystem of claim 24 wherein the valve body includes an outlet portsupplying untreated water from the supply port to the electrochemicaldeionization device and an input port supplying treated water from theelectrochemical deionization device to the point of use.
 26. The systemof claim 18 wherein the electrochemical deionization device is acapacitive deionization device with a flow-through capacitor.
 27. Amethod of treating and providing fluid from a point of entry to a pointof use, the method comprising: providing an electrochemical deionizationdevice between the point of entry and the point of use; coupling a valvebody to the electrochemical deionization device; and supplying treatedfluid from the electrochemical deionization device to the point of usethrough the valve body and simultaneously supplying untreated fluid fromthe point of entry to the point of use through the valve body in orderto blend untreated fluid with treated fluid when a valve of the valvebody is in a first position and when demand increases at the point ofuse.
 28. The method of claim 27 and further comprising supplyinguntreated fluid from the point of entry through the valve body to theelectrochemical deionization device when the valve is in a secondposition.
 29. The method of claim 28 and further comprising supplyingtreated fluid from the electrochemical deionization device through thevalve body to the point of use when the valve is in a third position.30. The method of claim 29 and further comprising bypassing theelectrochemical deionization device so that untreated fluid is suppliedfrom the point of entry to the point of use when the valve is in afourth position.
 31. The method of claim 30 and further comprisingbypassing the electrochemical deionization device due to a line energyloss.
 32. The method of claim 27 and further comprising treating fluidfrom the point of entry with a capacitive deionization device includinga flow-through capacitor.